Biomechanical variables including the masticatory forces on a dental implant, the implant geometry, and the resulting stresses and strains in interface tissues can determine the clinical success or failure of an endosseous dental implant. Up to now there has been inadequate characterization of masticatory forces on dental implants in various animal models. This has held back development of biomechanical design principles for dental implants. The goal of this research is to measure in vivo forces on dental implants as functions of (1) bridgework over the implant and (2) the animal model. In Year 1 of the grant the aim will be to measure only the apical force component on a dental implant in vivo. A transducer will be designed using strain gauge methods. It will then be attached to dental implants in animal mouths in order to measure bite forces on the implants. Wire from the transducer will be routed subcutaneously to each animal's back, and connected to appropriate electronics. In years 2 and 3 of the grant, the aim will be to apply the methods developed in Year 1 to investigate how the force components on a dental implant depend upon (1) the type of bridgework over the implant, and (2) the animal model. To attack the latter problem completely, a commercially-available implantable telemetry system will be adapted for use with instrumented implants, since hard-wiring will be impractical in animals such as baboons or monkeys that are commonly used in implant research. Development of the capability to measure in vivo forces on dental implants in various animal models will lead to future experiments aimed at defining the interactions between implant-tissue biomechanics and clinical performance of implants.